I always make sure the seller has 100% positive feedback, many sales, and I always message to ask if it's audibly graded. I only ever buy M/NM/EX+. The amount of times, after I've gone through all of the above, I've ended up with crackly, skipping, marked records is pretty unbelievable. I had one guy tell me that 'it's just part of the format, I've been dealing for 25 years', and another guy who accused me of 'materially altering' the records after his set of 12 LPs (which I paid several hundred dollars for), listed as NM, arrived in less than VG condition. I admitted that I'd used a carbon fiber brush on one record before I put on my turntable to test the quality. The rest were too grimy to touch. I had one guy tell me how a certain iconic intro to a record was 'pristine, loud and clear', and when it turned up that particular part was nothing but hiss and pops. I had another seller (from a small store but also on Discogs, no less), audibly test a 'NM' LP only for it arrive in 'VG' condition (which is useless for my purposes). He replied thus: "REFUNDREFUNDREFUNDREFUND!! HAVE A REFUND!!!!" So, yeah, there are a lot of time wasters out there, sadly. On the plus side - I've had a lot of good transactions, too. It's a shame that the bad ones tend to stick out in the memory.